Chosen Solution
I recently bought an Apple MacBook Air, and stupidly didn’t check to see if there was a firmware password on it or not. The old owner doesn’t know the password. So, I purchased a pre-loaded EFI chip for this specific model (a1466 EMC2632) and followed a tutorial on youtube on how to replace the EFI chip with a heat gun and flux. I did so, and I reassembled the logic board and doubled checked to make sure every cable was plugged in properly. I plugged in my MagSafe charger and it doesn’t show a green light. I pressed the power button and nothing came on, no sound, no battery symbol. I thought maybe the BIOS chip was bad, but would that prevent the entire computer from powering on? The battery is still good, the cables are all plugged in securely. I don’t know what exactly could be causing this, as I didn’t do anything other than heat up the EFI chip and replace it with a different one (which is from the same model MacBook Air). I know the charger works properly because it charges my MacBook Pro just fine. any suggestions? Is there something that could go wrong in re-mounting the logic board?
This could come from different things: your new bios chip is not proprely programed or erased or faultyyou inversed the chip position when mountingyou knocked down some little resistors surrounding the bios chip Recheck around the bios chip for missing components and then recheck the rest of the motherboard
You should have just flashed it not replaced it.
I know this is an old thread but I was curious to know how this worked out. Although there is a chosen solution, no one ever indicated what the problem actually turned out to be or what actions fixed it (a problem all too common on help forums). The things to look out for (and it sounds like you probably did, Tiffany) are making sure that the chip is oriented properly, that the solder pads are cleaned and fluxed before soldering, that each pin is soldered, that there is no solder between pins and that the chip is not overheated. There are many high-quality hot air stations that are quite affordable; just make sure that the air-flow can be set low, so as to avoid moving adjacent SMDs (surface-mounted devices) while working on the EFI chip. The ratings and reviews by other users will guide you. I use Kapton tape (a high-temp masking tape specifically for operations like this) and foil to mask off the surrounding area, if there are other SMDs too close to the work area. On a laptop, the components are often very close together; watch closely to make sure no adjacent components are moved; if they are, gently nudge them back onto place before removing the heat. About the power light; that actually sounds like something other than the EFI chip; the EFI chip contains the basic instructions that tell the system how to start up, test its basic hardware, detect the boot drive and start reading the OS into memory. The green LED is actually wired to the SMC chip, which illuminates the charger LED 1 second after the charger is connected (if all is well). See this article for more info. I hope all worked out well and, again, if you can, please let us know what the problem turned out to be and how it was fixed. Best Wishes!!
